I have an existing assembly that contains hundreds of classes. I'd like to run Pex against one class at a time but I can't figure out a way to do so. Any help in this regard would be greatly appreciated...
I tend to use the Unit Test Wizard that is built into the visual studio test tools to create a test for me for a particular class and methods when i want to do this. (Tests->New Test -> choose unit test wizard)
All a test class is is a class that has the [TestClass] attribute ... if you want a pex class just add the [PexClass] attribute.
Then you add your parameterized unit tests using the [PexMethod] attribute, it will generate tests wit the [TestMethod] attribute for you.
Related
I have to get the source code of a class, compile it and then execute a Junit test on it. I managed in many ways to compile dynamically my code, generating a .class file, so that's not the problem.
Since this procedure is done dynamically, how can I invoke methods and constructors of this class in the JUnit test case without using Java reflection?
I am not sure if what i am doing is actually the "correct" way of doing unit tests with DI. Right now i ask my ViewModelLocator to actually create all the instances i need, and just get the instance i need to test, which makes it very simple to test a single instance because lets asume that Receipt needs a Reseller object to be created, reseller needs a User object to be created, user need some other object to be created, which creates a chain of objects to create just to test one single instance.
With di usally interfaces will get mocked and parsed to the object which you would like to create, but how about simple Entities/ViewModels?
Whats the best practice to do unit testing with DI involved?
public class JournalTest
{
private ReceiptViewModel receipt;
private ViewModelLocator locator;
[SetUp]
public void SetUp()
{
locator = new ViewModelLocator();
receipt = SimpleIoc.Default.GetInstance<ReceiptViewModel>();
}
[TearDown]
[Test]
public void CheckAndCreateNewJournal_Should_Always_Create_New_Journal()
{
receipt.Sale.Journal = null;
receipt.Sale.CheckAndCreateNewJournal();
Assert.NotNull(receipt.Sale.Journal);
}
}
First, you aren't using Dependency Injection in your code. What you have there is called Service Locator (Service Locators create a tight coupling to the IoC/Service Locator and makes it hard to test).
And yes, it's bad (both Service Locator and Dependency Injection), because it means: You are not doing a UnitTest, you are doing an integration Test.
In your case the ReceiptViewModel will not be tested alone, but your test also tests the dependencies of ReceiptViewModel (i.e. Repository, Services injected etc.). This is called an integration test.
A UnitTest has to test only the class in question and no dependencies. You can achieve this either by stubs (dummy implementation of your dependencies, assuming you have used interfaces as dependencies) or using mocks (with a Mock framework like Moq).
Which is easier/better as you don't have to implement the whole class, but just have to setup mocks for the methods you know that will be required for your test case.
As an additional note, entities you'll got to create yourself. Depending on your UnitTest framework, there may be data driven tests (via Attributes on the test method) or you just create them in code, or if you have models/entities used in many classes, create a helper method for it.
View Models shouldn't be injected into constructor (at least avoided), as it couples them tightly
Units tests should run quickly and should be deterministic. That means you have to mock/stub everything that brokes these two rules.
The best way to mock/stub dependancies is to inject them. In the production, classes are assembled by DI framework, but in unit tests you should assemble them manually and inject mocks where needed.
There is also a classic unit test approach where you stub/mock every dependency of your class, but it's useless since you don't gain anything by that.
Martin Fowler wrote great article about that: link
You should also read Growing Object-oriented software: Guided by tests. Ton of useful knowledge.
What is the difference between Testng Class and a normal Java class. While creating an Automation suite in Selenium should we use Testng class or normal java class in Eclipse.
TestNg is not language it's a testing framework. See this
TestNG is a testing framework inspired from JUnit and NUnit
This is a framework to handle different kind of testing such as unit,end to end, functional and so more. It uses Java and provide supports and annotations to drive testings. That's it!
A TestNg class is a Java class, but a Java class does not have to be a TestNg class.
The following is from the TestNg documentation and gives an understanding what you can do with the TestNg class:
This class is the main entry point for running tests in the TestNG
framework. Users can create their own TestNG object and invoke it in
many different ways:
On an existing testng.xml
On a synthetic testng.xml, created entirely from Java
By directly setting the test classes
You can also define which groups to include or exclude, assign
parameters, etc...
From: http://testng.org/javadoc/org/testng/TestNG.html
TestNg is basically is a set of code written in Java that allows you to create tests.
A TestNG class is a Java class that contains a method annotated by this class: org.testng.annotations.Test;
Testng Class and a normal Java class
TestNG Class: TestNg class is nothing but any normal class with TestNG annotation and Annotation is a tag that represents the metadata which gives the addition information about class, methods and interface.
To know more about annotation Please refer this https://docs.oracle.com/javase/tutorial/java/annotations/
While creating Automation suite we use either JUNIT or TestNG. JUNIT or TestNG are testing framework. They have their own set of libraries and annotations which is useful to run our automation suite. JUNIT or TestNG makes easy to run automation suite or generate reports of build run. They provide the feature to setup or cleanup activity using Before and After annotation which is require in almost every autoamtion suite.
TestNG also provide us flexibility to execute our automation script based on our requirement like we can group of test cases, we can include or exclude methods, parallel execution of test methods and many more.
Please refer this to know more about TestNG.
http://testng.org/doc/documentation-main.html
I hope this will help.
I am working with testNG where I run an external test framework, receive the result data and assert it. To run the external test framework I need to set up a specification for which tests that should be run. To generate this specification I need to know which tests that are selected in the testNG .xml file.
The only way I could think of doing this is to parse the file manually. But I am hoping for a better solution than this.
Thanks for any answers!
//Flipbed
Edit:
My colleague found solutions to the problem.
In #Factory and #DataProvider annotated methods it is possible to add a parameter of the type ITestContext. Using the variable of that type, one can use the method .getAllTestMethods().
Create a new class that implements IMethodInterceptor. In this class one can override the method 'intercept'. The method takes a parameter of the type List which is a list of all methods that will be run by testNG.
If someone has any other suggestions feel free to add.
//Flipbed
The solution that we used was to number 2 in my edit. We implemented the IMethodInterceptor and used the methods list as well as the ITestContext to both view what tests will run and modify that list.
I know it may sound like a silly question as I've heard many saying that you should only do unit testing for public function and indeed, visual basic.net in Visual studio IDE only allows me to do unit testing for public function.
However, I got a public function that is calling to many other private functions.
If I do unit testing for that public function, that would be too complicated. I only want to test each private function individually to make sure it works correctly first, before jumping to the parent public function.
One solution I've had in my mind is that I could change all private functions to public ones so that Visual Studio allows me to do unit testing for them. But it is annoying me as I don't want them to be public.
Is there any suggestions you could let me know please?
many thanks in advance.
N.T.C
If you really can't break the code out into separate classes, you could change all of the private functions to be protected and then create a private class within your test class that inherits from the class you're trying to test (this would be named as a fake or stub, hence my advice to make it private. You don't want code outside of the test class to interact with this). Within your inherited class, create public functions for each of the now protected functions that simply call through to the base and write your unit tests against those instead.
I apologize if this capability is not available in VB:
Create a sub-class of the class you want to test. Ensure that the sub-class has public interfaces to the private functions.
As for "only unit test public functions?" That's horse manure. You test what might fail. For instance, you might have a class with only one public function, and you want to refactor into a set of calls on private functions to decrease the complexity. If you have to refactor your solution for any reason (as one of the comments suggested), then the first step is to have all the pieces of the solution tested that you will have to change during the refactoring.